Film holder for dental work



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tag M! d ATTORNE Jan. 24, 1928. I

F. v. SIMONTON FILM HOLDER FOR DENTAL WORK Filed Jan; 19. 1926 Patented Jan. 24, 1928.

UNITED STATES i,e57,230 PATENT oFF FRANK V. SIMONTON, 0F ROSS, CALIFORNIA, ASSIGNOR TO THE REGENTS OF THE UNIVERSITY OF CALIFORNIA, A CORPORATION OF CALIFORNIA.

FILM HOLDER FOR DENTAL WORK.

Application filed January 19?, 1926. Serial No. 82,213.

This invention relates to a holder whereby a film may be held and replaced in a predetermined position with relation to the teeth and X ray projector when making an exposure. In the treatment of pyorrhea and particularly in research worl: where a radio graphic method of examination is conducted,

it is very importantto be able to determine accurately, and to record the extent of destructive changes of the investing tissues previous to treatment, at intervals during treatment and at the conclusion of treatment. It is only upon the basis of such determinations and records that one is justified in drawing conclusions concerning improvements, continued destructive changes or the maintenance of status quo. This means that an operator mustbe able to positively control the several variables encountered. For instance amperage, time of exposure of films,

the type, strength, temperature, etc. of de veloper and time of development. Such variables are readily controlled with modern machines and are easily standardized, but there areother variables, namely, the relation of film, teeth and machine which have heretofore presented considerable diificulty. The invention forming the subject matter of the present application has overcome this difficulty. It consists in providing afilm holder whereby predetermined relation of film, teeth and machine may be obtained with absolute accuracy thereby permitting roentgenographs to be reproduced under identical conditions from time to time as the treat- I ment proceeds.

One form whichthis film holder may assume is exemplified in the accompanying drawings in which- Fig. 1 is a side elevation of the film holder partly in section showing it in position within the mouth and positively adjusted with relation to the teeth and the compression cone on the machine.

, Fig. 2 is a front elevation of the teeth of the patient showing the film holder in dotted lines and the bite plate in longitudinal section. i j v Fig. 3 is a plan view of Fig. 1 showing the film holderand bite plateremoved.

Fig. 4; is a perspective view of the film holder. Fig. 5 plate. l

Referring to the drawings in detail, Fig.

is a perspective View otthe bite 1, A indicates the compression cone of an X ray machine, 2 the upper and 3 the lower teeth oi the patient from which a radiograph record is to be made. B indicates in general the mouth piece or film holder placed in position within the mouth of the patient and C a: graduated swivel head whereby the film holder is adjusted with relation to the teeth and the compression cone. The film holder proper consists of a plate 4. such as shown in Fig. i, on the sides of which areiornied flanges 5 to receive and secure the X ray film. Secured to the upper end of the plate is a cross bar 6 on which are formed two arms 7 and 8. The outer surfaces of the arms are provided with grooved guideways 9 to receive a bite plate generally indicated at' 10 and the outer ends of the arms are provided with drilled openings 11 to receive pins 12 carried by a supporting arm 13. The bite plate is nothing more or less than a shallow tray having guide flanges 14 at opposite ends to be received by the guideways 9 of the arms 7 and 8 and side flanges 15 to receive and secure modeling compound such as shown at 16. p i

j A film holder together with a bite plate forms a complete mechanism whereby a film may be supported with relation to the teeth or tissues to be radiographed, but accurate results cannot be obtainedwith these two devices alone as it would be impossible to secure a predetermined position with relation to the teeth and the machine. To secure such predetermined position the swivel head C has been provided. The swivel head carries a threaded pin 17 on which is turnably mounted an arm 18. This arm is carried by a bracket 19 secured to the compression cone and it is longitudinally adjustable in the bracket as shown and may be secured in any longitudinal adjusted position by means of a set screw 20. The outer end of the rod 18 is enlar ed to form ahead 21 which cooper ates with the swivel head C. The threaded screw 17 passes through the heads G and 21 and a clamping nut 22 is employed to secure said heads when an adjusted position is assumed. Both heads are provided with graduations as indicated at 23 and a record may therefore be made of their related positions. The head C is provided with a ertorated lug 24, this lug being provided or the reception of the arm 13. The arm is provided with a square shank 25 which extends through the lug and the outer end of the shank is threaded to receive a clamping nut 26.

Arms 13 and 18 together with the swive head C is the mechanism reliedupon to obtain a predetermined position between the teeth, film and machine. In making an exposure with this device the procedure is as follows. A film is placed between the guide flanges 5 of the plate l, amodeling compound softened by heating is placed in the tray between the side flanges and the tray is then placed on the arms 7 and 8 by passingthe guide flanges 14L into the guideways 9. The iihnholder together with the tray and modeling compound in position is then placed in position in the month and. in proper relation to the teeth so as to get an impression of several teeth. The compound isthen ,chilled which hardens it and fixes these imprints. The film holder and tray may now be removed and replaced at will. The compression cone is. now focused, this being accomplishedby loosening the nuts and 22, loosening of nut 20 permits longitudinaladjustment and loosening of the nut .ZQgangular adjustment. when the proper focus is made with relation to the film holder, the nuts are tightened and an exposure is ready to be made; The tray carrying the modeling compoundis replaced on the film holder and the entire device is again placed in the mouth of the patient. A roll of cotton wadding or the like such as indicated at 28 is placed on top oi the arms 7 and 8. y The patient is then instructed wise.

down on the device as a whole to hold it securely in place. The pins 12 of arm 13 are then fitted into holes 11 of arms 9 of mouthpiece B, thus attaching the mouthpiece to the compression come. The exposure may then be made and the device is removed by the patient opening the mouth widely and backing away from the film holder. A record is made of the longitudinal adjustment and theswivel head adjustment and the bite plate or tray 10 is retained for future use.

The tray 10 is made in quantity and aseparate plate is used for each patient as it is obviously necessary to take radiographs from time to time as the treatment proceeds. \Vhen making the impression in the modeling compound when the first exposure is to be taken as few teeth are included in the impression as are essential to obtainfstability and correct position, the reason being that the teeth are apt to move in the arches in the courseof time and slight changes in position of a number ofteeth might prevent the impression from goin to place when a subsequent picture is talien. For instance, after an elapse of six months or a year. Y

Where it is desired to obtain fine detail of pockets formed in the tissue between the teeth by pyorrhea, the saii ie is accomplished by inserting a pin 30 into the pyorrhea. pocket such-as indicated at 531., the ob ect being to ascertain anychange in the exact depth of the pocket as subsequent radiographs are taken. A pin when inserted should also be held in a predetermined position with relation to the film andl'he inaehine and means are accordingly provided for obtaining such prerletcrmined position. This is accomplished by providing a. central opening l0 in the tray, themodcling compound in register with this hole is cut out as indicated by tliesti'aiglit lines at 32. A small tube :33 is placed between the teeth and the pin 30 is inserted through the tube andinto the pocket 31. Plaster o'l Paris or a like compound is then poured into the open ing as indicated at 34 and permitted to set. The setting of the plaster of Paris determines not only the position of the tube but also the pin, because if the pyorrhea pocket heals up or disappears the pin will project further up into the tube and each radiograph taken will show the place of healing.

After an exposure has been taken it is necessary to remove the bite plate and the lilm holder, thisbeing accomplished by pulling the wire pin 30 back into the tube or completely out of the same to protect it from bending. In taking a second picture the film holderand biteplate are placed in position and as it carries the tube 33 the tube will be in direct position with relation to the pyorrhea pocket 31 and it is, thus'possible to readily reineert the wire or pin 30.

The degree of accuracy possible with a device of this character has been well, established as a number of double exposures have been made without any blur resulting.

\Vhile this device is primarily designed for use in pyorrhea it is equally applicable in all cases where it is desired to compare roentgenographs. taken at different times of the same region. Such roentgenographs are only comparable when taken under conditions which permit control of all of the variables.

Having thus described my invention what I claim. and desire to secure by Letters Pateat is n .1. In a device of the character described, the combination with the compression cone of an X ray machine of a film holder adapted to be placed in the mouth of a patient rearwardly of the teeth to be radiographed, a bite plate carried by the film holder and adapted to receive and maintain the impression of a number of teeth to secure the film holder in a predetermined position with relation to the teeth, a tube adapted to be secured in a predetermined position in the bite plate so as to assume a predetermined position with relation to the teeth, a pin insertable through the tube and means whereby a prelllO determined position may be maintained between the compression cone the teeth; the pin and the film holder. I

2. In a device of the character described the combination with the compression cone of an X-ray machine of a bearing bracket secured to one side thereof, a rod longitudinally adjustable .in said bearing bracket and extending forwardly from the cone at one side thereof, said rod terminating in a swivel bearing plate, a swivel head secured to the swivel bearing plate and turnable with relation thereto to assume different angles. means whereby the head may be secured against turning when a desired angle is bite plate and film holder adapted to be se cured to said rod.

FRANK v. SIMONTON. 

